TWI254717B - Method for the preparation of pentafluorophenylacrylate polymer - Google Patents

Abstract

A method for synthesizing a pentafluorophenylacrylate polymer includes bulk polymerizing a pentafluorophenylacrylate monomer in the presence of a free radical initiator. The reactant mixture was subjected to an ultrasonication treatment, so that the mixing of the initiator and the monomer is enhanced; carried out the bulk polymerization at 25-99 DEG C for a period of time, and at 100-200 DEG C under a vacuum pressure for another period of time to complete the bulk polymerization, so that residue amounts of the initiator, unreacted monomer and oligomer of the monomer are reduced in the resulting reaction mixture.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for synthesizing a pentafluorophenyl acrylate polymer, and more particularly to a method for synthesizing a pentafluorophenyl acrylate polymer by overall polymerization. The prior art acrylate polymer is highly translucent and suitable for long-distance optical telecommunication materials, but because it contains many CH bonds in the molecule, it absorbs the wavelength used for information transmission ι·2~1·6/ζ m, causing optical loss, and the fluoroacrylate polymer contains only a small amount of CH bonds, which greatly reduces this disadvantage, so it is often developed as a light transmission material, and polyfluorophenyl acrylate polymer is one of them. . According to the prior art publication method, the polymerization reaction of pentafluorophenyl acrylate monomer has two types: solution polymerization and bulk p〇 lymerization. • Example 25 of the European patent Ep 〇 824 〇 96 (1998) is a thermal radical initiator (themai initiat 〇r) 2,2,-azobisisobutyronitrile (2,2'-azobisisobutyronitrile, AIBN) The free radical initiator is polymerized with a 0.54% molar percentage of AIBN* pentafluorophenyl acrylate monomer in a 2-butyr solution, and the solvent is removed after the reaction, and the residue is removed. Dissolved in tetrahydrofuran, and then added with methanol for re-precipitation; /λ was removed from the unreacted 70 monomer and short-chain polymer. The precipitate was taken up in a vacuum and dried in vacuo to give a polymerized product. The yield was 66%. This method uses organic solvents for both polymerization and post-treatment, which has an environmental impact, and the 1254717 procedure is more complicated. French patent FR26235 10 (1 989) and J. Fluorine Chem., 97, 191 (1999) use the overall polymerization method, in which the former uses fluoropropene fluorene monomer and AIBN and a small amount of bond transfer agent (dodecane thiol) polymerize together; the latter is a two-stage reaction by mixing a fluoroacrylate monomer with a photoinitiator and a thermal radical initiator, although the overall polymerization does not use an organic solvent, and the operation is simple. However, the unreacted monomer and the low degree of polymerization product remain in the polymer, which may affect product quality and heat resistance, and is not conducive to subsequent processing. SUMMARY OF THE INVENTION The present invention provides a method for synthesizing a pentafluorophenyl acrylate polymer comprising an overall polymerization reaction comprising a reaction mixture of a pentafluorophenyl acrylate monomer and a radical initiator, wherein the radical initiator Insoluble or only partially soluble in the pentafluorophenyl acrylate monomer, characterized by comprising ultrasonically oscillating the reaction mixture to promote the radical initiator and the pentafluorophenyl acrylate Mixing of monomers; performing the overall polymerization reaction for a period of time between 25 and 2 Torr (the first temperature of rc; and a second polymerization at a second temperature of 25 to 200 C and a vacuum pressure) - completing the overall polymerization reaction for a second period of time 'thus reducing the total amount of the free radical initiator, the unpolymerized monomer or the oligomer of the monomer in the product mixture of the reaction. Preferably, The radical initiator is 2,2,,nitrobisisocyanenitrile (AIBN) 〇1254717. Example 1 is 1.74 g (6 mmol) of pentafluorophenyl acrylate monomer, and 0.006 g (0.036 mmol) with AIBN. Hybrid to ultrasonic vibration After 1.5 minutes, the reaction was heated at 60 ° C for 12 hours under nitrogen, and the reaction was continued at 0.3 mmHg / 140 ° C for 12 hours to obtain a transparent polymerization product. Figure 1 shows the transmittance of the transparent polymerization product at different wavelengths. The molecular weight of the polymer was measured by gel permeation chromatography (GPC). The results are as follows: number average molecular weight weight average molecular weight molecular weight peak dispersion Μη Mw Mp (polydispersity) 26379 89254 132091 3.28 Polymeric heat The results were measured by Thermogravimetric analysis (TGA). The results showed that the weight loss of the polymer when heated to 277 ° C was 1.6%, and the weight loss was 5% at 344 ° C. Comparative Example 1 took pentafluorophenyl acrylate. The ester monomer was 1.74 g (6 mmol), mixed with AIBN 0.006 g (0.036 mmol), ultrasonically shaken for 1.5 minutes, and heated under nitrogen at 60 ° C for 24 hours to obtain a transparent polymerization product. The heat resistance was analyzed by TGA, and as a result, the weight loss was 5.1% by heating to 272 ° C, and the weight loss was 10.2% by 344 ° C. Compared with the comparative example, the first example of the present invention was significantly superior. Heat. 1,254,717 transmittance drawings briefly described an example different wavelengths of synthetic polymeric product of the present invention in FIG.

Claims (1)

¢54 娜. Pick up, the scope of application for patents: 1 · A method for forming a polymer of propylene sulfide pentafluorophenyl ester, comprising a total polymerization reaction comprising a pentafluorophenyl acrylate monomer and a radical initiator The reaction mixture 'the free radical initiator in the crucible is insoluble or only partially soluble in the pentafluorophenyl acrylate monomer, and the characteristic comprises - ultrasonically oscillating the reaction mixture to promote the radical Mixing the initiator with the pentafluorophenyl acrylate monomer; performing a total polymerization reaction at a first temperature of one (eight) for a first period of time; and a second temperature between 25 and 2 Torr And performing the overall polymerization reaction for a second period of time under a λ air pressure to complete the overall polymerization reaction, thereby reducing the radical initiator, the unpolymerized monomer or the monomeric oligomer in the product mixture of the overall polymerization reaction. Residue of the polymer. 2. The method of claim 2, wherein the radical initiator is 2,2'-azobisisobutenenitrile (oxime). 3. If you apply for a patent scope! Or the method of item 2, wherein the molar ratio of the radical initiator to the pentafluorophenyl g propyl monomer in the reaction mixture is 〇·6:1 〇〇 to ι:1. 4. The method of claim 3, wherein the molar ratio of the radical initiator to the pentafluorophenyl acrylate monomer in the reaction mixture is 〇.6:1〇〇〇1254717 (2005) Amendment in October of the year) 5. The method of claim 1, wherein the second temperature is 100-200 ° C, the vacuum pressure is 0.1-3 0 mmHg, and the second period is 4-36 hours . 6. The method of claim 5, wherein the second temperature is 140 ° C, the vacuum pressure is 0.3 mmHg, and the second period of time is 12 hours. 7. The method of claim 5, wherein the first temperature is 2 5-99 ° C, and the first period is 4-36 hours. 8. The method of claim 7, wherein the first temperature is 60 ° C and the first period of time is 12 hours.